package polymorphism;
import static net.mindview.util.Print.*;

class Actor{
	public void act(){}
}
class HappyActor extends Actor{
	public void act(){
		print("HappyActor");
	}
}
class SadActor extends Actor{
	public void act(){
		print("SadActor");
	}
}
class Stage{
	private Actor actor= new HappyActor();
	public void  change(){
		actor = new SadActor();
	}
	public void performPlay() {
		actor.act();
	}
}
public class Transmogrify {
   public static void main(String[] args) {
	 Stage stage = new Stage();
	 stage.performPlay();
	 stage.change();
	 stage.performPlay();
   }
}
